044  
FXUS02 KWBC 060028  
PMDEPD  
 
EXTENDED FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
728 PM EST WED JAN 05 2022  
 
VALID 12Z SUN JAN 09 2022 - 12Z THU JAN 13 2022  
   
..GENERAL PATTERN OVERVIEW
 
 
AN AMPLIFIED BUT PROGRESSIVE UPPER LEVEL PATTERN SHOULD PREVAIL  
INTO THE START OF NEXT WEEK WITH A DEEP TROUGH TRACKING FROM THE  
ROCKIES TO THE EAST COAST AND A RIDGE AXIS MOVING INTO THE WESTERN  
U.S. FROM THE EASTERN PACIFIC. BY EARLY-MID WEEK THE PATTERN  
SHOULD TRANSITION SOMEWHAT AS EASTERN PACIFIC SHORTWAVE ENERGY  
SPLITS AROUND THE WESTERN U.S. RIDGE--LEADING TO A POSSIBLE  
SOUTHERN STREAM TROUGH REACHING THE SOUTHWESTERN U.S. AND FAR  
NORTHWESTERN MEXICO--AND A FLATTER TREND TO THE MEAN FLOW ACROSS  
THE EASTERN HALF OF THE COUNTRY. THE MAIN PRECIPITATION EVENT  
DURING THE PERIOD WILL BE AN AREA OF LOCALLY MODERATE TO HEAVY  
RAINFALL OVER PARTS OF THE SOUTH/TENNESSEE VALLEY THIS WEEKEND,  
AIDED BY MOIST FLOW AHEAD OF A COLD FRONT. ANOTHER SURGE OF COLD  
AIR WILL SPREAD ACROSS THE NORTHERN PLAINS THROUGH THE UPPER  
MIDWEST SUNDAY INTO THE FIRST PART OF NEXT WEEK, FOLLOWED BY A  
WARMER TREND OVER THE CENTRAL U.S.  
   
..GUIDANCE/PREDICTABILITY ASSESSMENT
 
 
GUIDANCE CONTINUES TO BE WELL-BEHAVED IN TERMS OF AGREEMENT AND  
CONTINUITY FOR ABOUT THE FIRST HALF OF THE PERIOD WHEN THE PACIFIC  
INTO WESTERN U.S. UPPER RIDGE AND DOWNSTREAM TROUGH ARE DOMINANT  
AND LARGE-SCALE FEATURES. LIKEWISE FORECASTS FOR THE COLD FRONT  
AHEAD OF THE UPPER TROUGH ARE FAIRLY CONSISTENT. A BLEND OF  
00Z/06Z OPERATIONAL MODELS REFLECTED CONSENSUS WELL FOR THIS PART  
OF THE FORECAST. THEN MODELS AND ENSEMBLE MEMBERS CONTINUE TO  
VARY FOR SPECIFICS OF HOW EASTERN PACIFIC SHORTWAVE ENERGY MAY  
SPLIT AS IT NEARS THE WEST COAST. THESE DIFFERENCES ULTIMATELY  
AFFECT FLOW OVER/NEAR THE SOUTHWEST AS WELL AS LOCATIONS EAST OF  
THE ROCKIES, WITH NORTHERN STREAM FLOW DETERMINED IN PART BY HOW  
PACIFIC ENERGY GOES AROUND THE WESTERN U.S. RIDGE AND SOUTHERN  
TIER FLOW INFLUENCED BY THE PATTERN TO THE WEST. FOR THIS MORE  
UNCERTAIN PART OF THE FORECAST, TRANSITIONING TO A BLEND OF MODELS  
AND GEFS/ECMWF MEANS HELPED TO KEEP THE OVERALL EVOLUTION FAIRLY  
STABLE WITH ONLY MODEST REFINEMENTS IN DETAIL.  
   
..HAZARDS/SENSIBLE WEATHER HIGHLIGHTS
 
 
GULF MOISTURE ADVECTING NORTHWARD AHEAD OF A DEVELOPING  
PLAINS/MIDWEST COLD FRONT WILL SUPPORT INCREASING COVERAGE OF  
SHOWERS AND THUNDERSTORMS FROM EASTERN TEXAS AND THE CENTRAL GULF  
COAST TO THE OHIO VALLEY AND MID-ATLANTIC REGION THIS WEEKEND,  
WITH LIGHTER RAINFALL EXPECTED FARTHER NORTH. THERE WILL LIKELY  
BE SOME EMBEDDED HEAVIER RAINFALL ACROSS PORTIONS OF THE DEEP  
SOUTH WHERE CONVECTION IS PERSISTENT. AREAS FROM THE UPPER GREAT  
LAKES TO THE NORTHEAST COULD SEE WINTRY WEATHER, WITH THE BEST  
SNOWFALL PROSPECTS OVER NORTHERN NEW ENGLAND AND NORTHERN NEW  
YORK. FREEZING RAIN AND/OR SLEET MAY BE AMONG THE HAZARDS OVER  
AND NEAR PARTS OF THE NORTHERN HALF OF THE APPALACHIANS FOR A TIME  
AS MOISTURE OVERRUNS COLD AIR AT THE SURFACE. PARTS OF THE GREAT  
LAKES MAY SEE LAKE EFFECT SNOW BEHIND THE PASSING FRONT. DRY  
CONDITIONS WILL LIKELY PREVAIL OVER A MAJORITY OF THE LOWER 48  
DURING THE FIRST HALF OF NEXT WEEK. EXCEPTIONS INCLUDE SOME  
SHOWERS AND MOUNTAIN SNOW OVER WESTERN WASHINGTON AND OREGON AS  
ONE OR MORE SYSTEMS BRUSH THE REGION AND SOME PRECIPITATION  
SPREADING INTO THE SOUTHWEST AND SOUTHERN PLAINS. PRECIPITATION  
AMOUNTS WILL BE SENSITIVE TO THE EXACT DETAILS OF THE UPPER TROUGH  
APPROACHING/REACHING THE SOUTHWEST.  
 
ON SATURDAY THE PLAINS/MIDWEST WILL SEE SOME MODERATION OF THE  
SEVERE COLD BEFORE THE NEXT ARCTIC SURGE REACHES INTO THE NORTHERN  
TIER STATES BY SUNDAY INTO TUESDAY MORNING. THE SECOND SURGE MAY  
NOT BE QUITE AS INTENSE AS WHAT IS EXPECTED FOR THE END OF THIS  
WEEK, BUT TEMPERATURES COULD STILL BE 10-25F BELOW NORMAL FROM  
EASTERN MONTANA TO WISCONSIN. THE COLD AIR WILL EVENTUALLY REACH  
THE EAST COAST AS WELL, BRINGING HIGHS DOWN TO 10-25F BELOW NORMAL  
FROM THE MID-ATLANTIC THROUGH NEW ENGLAND ON TUESDAY. FROM  
SATURDAY INTO SUNDAY ABOVE NORMAL TEMPERATURES WILL PROGRESS FROM  
THE SOUTHERN PLAINS TO THE DEEP SOUTH AND SOUTHEAST U.S. GREATEST  
ANOMALIES SHOULD BE FOR OVERNIGHT LOWS 15-25 DEGREES ABOVE NORMAL  
ACROSS THE CENTRAL GULF COAST REGION SUNDAY MORNING. THE  
NORTHERN-CENTRAL PLAINS WILL TREND WARMER NEXT WEEK, REACHING  
10-15F OR SO ABOVE NORMAL OVER SOME LOCATIONS BY  
TUESDAY-WEDNESDAY. SEASONABLY COLD CONDITIONS ARE LIKELY WEST OF  
THE CONTINENTAL DIVIDE WITH READINGS GENERALLY WITHIN 10 DEGREES  
OF CLIMATOLOGICAL AVERAGES.  
 
RAUSCH/HAMRICK  
 
ADDITIONAL 3-7 DAY HAZARD INFORMATION CAN BE FOUND ON THE WPC  
MEDIUM RANGE HAZARDS OUTLOOK CHART AT:  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/THREATS/THREATS.PHP  
 
HAZARDS:  
- FREEZING RAIN AND SLEET ACROSS PORTIONS OF THE CENTRAL  
APPALACHIANS AND THE NORTHEAST, SUN, JAN 9.  
- HEAVY RAIN ACROSS PORTIONS OF THE SOUTHEAST, THE SOUTHERN  
APPALACHIANS, THE LOWER MISSISSIPPI VALLEY, THE SOUTHERN PLAINS,  
AND THE TENNESSEE VALLEY, SAT-SUN, JAN 8-JAN 9.  
- HEAVY SNOW ACROSS PORTIONS OF THE GREAT LAKES, SUN-MON, JAN  
9-JAN 10.  
- FLOODING POSSIBLE ACROSS PORTIONS OF THE SOUTHEAST, THE  
MID-ATLANTIC, AND THE PACIFIC NORTHWEST.  
- FLOODING OCCURRING OR IMMINENT ACROSS PORTIONS OF THE PACIFIC  
NORTHWEST AND THE OHIO VALLEY.  
- FLOODING LIKELY ACROSS PORTIONS OF THE PACIFIC NORTHWEST AND THE  
OHIO VALLEY.  
- MUCH BELOW NORMAL TEMPERATURES ACROSS PORTIONS OF THE NORTHERN  
PLAINS AND THE NORTHERN ROCKIES, SAT-SUN, JAN 8-JAN 9.  
- MUCH BELOW NORMAL TEMPERATURES ACROSS PORTIONS OF THE NORTHERN  
PLAINS, THE UPPER MISSISSIPPI VALLEY, AND THE GREAT LAKES,  
SUN-TUE, JAN 9-JAN 11.  
- MUCH BELOW NORMAL TEMPERATURES ACROSS PORTIONS OF THE GREAT  
LAKES, MON-TUES, JAN 10-JAN 11.  
- MUCH BELOW NORMAL TEMPERATURES ACROSS PORTIONS OF THE NORTHEAST  
AND THE GREAT LAKES, TUE-WED, JAN 11-JAN 12.  
- HEAVY PRECIPITATION ACROSS PORTIONS OF THE ALASKA PANHANDLE AND  
MAINLAND ALASKA, SAT-TUE, JAN 8-JAN 12.  
- HIGH WINDS ACROSS PORTIONS OF THE ALASKA PANHANDLE AND MAINLAND  
ALASKA, SAT-SUN, JAN 8-JAN 9.  
- MUCH BELOW NORMAL TEMPERATURES ACROSS PORTIONS OF MAINLAND  
ALASKA, SAT-SUN, JAN 8-JAN 9.  
- MUCH BELOW NORMAL TEMPERATURES ACROSS PORTIONS OF MAINLAND  
ALASKA, SAT, JAN 8.  
 
WPC MEDIUM RANGE 500MB HEIGHTS, SURFACE SYSTEMS, WEATHER GRIDS,  
QUANTITATIVE PRECIPITATION, WINTER WEATHER OUTLOOK PROBABILITIES  
AND HEAT INDICES ARE AT:  
 
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST500_WBG.GIF  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/MEDR/5DAYFCST_WBG_CONUS.GIF  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/5KM_GRIDS/5KM_GRIDSBODY.HTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/QPF/DAY4-7.SHTML  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/WWD/PWPF_D47/PWPF_MEDR.PHP?DAY=4  
HTTPS://WWW.WPC.NCEP.NOAA.GOV/HEAT_INDEX.SHTML  
 

 
 

 
 
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